I don't know exactly what you mean but the size of a group affects its defense because there is a larger group. Therefore, more people would be protecting it, adding more to its defense.
Explanation:
The new research carried out by NASA on mars suggets that many of the Mars' ancient channel have been carved by flowing water, were actually formed by melt water beneath glacial ice sheets. The rocks looked familiar to the rocks found on Earth in these water channels. Moreover, conglomerate rock was found near the base of the channel on Mars.
<span>This is due to much of the energy that is consumed by lower trophic levels of the food chain/food web being used at that lower level. This energy is stored or used and, therefore, unavailable to the organisms higher up in the chain. As the chain lengthens, less energy is available, usually as a factor of 10 (1/10 of the energy taken in by the level below the consumer is available to the consumer's level, for example).</span>
